<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <select name="" id="">
        <option value="">-请选择地区-</option>
        <!-- 默认选项 -->
        <option selected>江西</option>
        <option value="">北京</option>
        <option value="">湖南</option>
        <option value="">浙江</option>

    </select>
    <input type="radio" name="sex" id="nan"><label for="nan">男</label>
    <input type="radio" name="sex" id="woman"><label for="woman">女</label>
    <br>
    <textarea rows="5" cols="20" placeholder="请输入留言"></textarea>
    <br>
    <input type="text" placeholder="请输入用户名" required pattern="^[a-zA-Z][a-zA-Z0-9]\w{6,10}$">
</body>

</html>